I have a book, somwhere...lol and it tells you how many calories you burn doing normal everyday activities. And it shows the different amount of calories you burn in the different ways you approach every day things. Sex is a great way to keep in shape actually. You notice how much strength and endurance you really need. I ride my bike for 2 miles and run 3 miles every day. Sex is great now bc I can keep up and even out do my partner. It's great.